I am currently looking for a gnome replacement,
I need the taskbar item rearrangement feature more than anything else, I have tried several and I have not found any that support that option by default except for gnome, Can someone please tell me which window managers have that option by default and if it is possible to implement it in different window managers that do not support that by default(say xfce or lxde)

I think what the OP means is the possibility to rearrange the representation of the windows in the taskbar.
In XFCE, when I open a programme, there appears an entry in the taskbar and if for some reason I minimize the window or put another one on top of it, I can get back to the window of that app by pressing the corresponding entry in the taskbar. Every other programme I start will also get an entry, and they're arranged in the order in which I started the programmes/ opened windows.
If you do anything that involves frequent switching between windows, it is nice to have them in the order you like. In Gnome you can just drag and drop the taskbar entries from one place to the other.

@blakdeath
You can run the Gnome panel in another DE. For example, if you prefer XFCE over Gnome, you can replace the XFCE panel with the gnome one.
You could also use Mate in Gnome's stead. It's a fork of Gnome 2.3x, made by people who were unsatisfied with Gnome 3/ preferred the Gnome 2.3x approach._________________Kali Ma
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